OJMI  Vol.4 No.3 , September 2014
Simultaneous Echo Refocused Magnetization Transfer Imaging
Author(s) Claus Kiefer
ABSTRACT
Purpose: To increase the efficiency of densely encoded magnetization transfer imaging of the brain, we time-multiplex multiple slices within the same readout using simultaneous echo refocusing FLASH imaging with magnetization transfer (MT) preparation (MT-SER-FLASH). Materials and Methods: Inefficiency in total scan time results from the number of frequency samples needed for sufficient quality of quantitative parameter maps for a binary spin bath model. We present a highly efficient multiplexing method, simultaneous echo refocused magnetization transfer imaging (MT-SER-FLASH) for reducing the total scan time of MT imaging by one-third. The specific absorption rate (SAR) was also reduced by reducing the number of MT-pulses per volume. Results: 2D-MT-SER-FLASH is performed in 19 minutes rather than 1 hour, acceptable for routine clinical application. The SAR could be reduced to 69% instead of more than 100% with a standard 2D or 3D-FLASH with MT-preparation. Conclusion: The net reduction of scan time and SAR enables the use of quantitative model based magnetization transfer imaging within a clinical environment.

Cite this paper
Kiefer, C. (2014) Simultaneous Echo Refocused Magnetization Transfer Imaging. Open Journal of Medical Imaging, 4, 154-158. doi: 10.4236/ojmi.2014.43021.
References
[1]   Pike, G.B. (1996) Pulsed Magnetization Transfer Contrast in Gradient Echo Imaging: A Two Pool Analytic Description of Signal Response. Magnetic Resonance in Medicine, 36, 95-103.
http://dx.doi.org/10.1002/mrm.1910360117

[2]   Sled, J.G. and Pike, G.B. (2000) Quantitative Interpretation of Magnetization Transfer in Spoiled Gradient Echo MRI Sequences. Journal of Magnetic Resonance, 145, 24-36.
http://dx.doi.org/10.1006/jmre.2000.2059

[3]   Sled, J.G. and Pike, G.B. (2001) Quantitative Imaging of Magnetization Transfer Exchange and Relaxation Properties in Vivo Using MRI. Magnetic Resonance in Medicine, 46, 923-931.
http://dx.doi.org/10.1002/mrm.1278

[4]   Kiefer, C., Brockhaus, L., Cattapan-Ludewig, K., Ballinari, P., Burren, Y., Schroth, G. and Wiest, R. (2009) Multiparametric Classification of Alzheimer’s Disease and Mild Cognitive Impairment: The Impact of Quantitative Magnetization Transfer MR Imaging. Neuroimage, 48, 657-667.
http://dx.doi.org/10.1016/j.neuroimage.2009.07.005

[5]   Cercignani, M. and Alexander, D.C. (2006) Optimal Acquisition Schemes for in Vivo Quantitative Magnetization Transfer MRI. Magnetic Resonance in Medicine, 56, 803-810.
http://dx.doi.org/10.1002/mrm.21003

[6]   Reese, T.G., Benner, T., Wang, R., Feinberg, D.A. and Wedeen, V.J. (2009) Halving Imaging Time of Whole Brain Diffusion Spectrum Imaging and Diffusion Tractography Using Simultaneous Image Refocusing in EPI. Journal of Magnetic Resonance Imaging, 29, 517-522.
http://dx.doi.org/10.1002/jmri.21497

[7]   Feinberg, D.A., Reese, T.R. and Wedeen, V.J. (2002) Simultaneous Echo Refocusing in EPI. Magnetic Resonance in Medicine, 48, 1-5.
http://dx.doi.org/10.1002/mrm.10227

[8]   Feinberg, D., Reese, T.G. and Wedeen, V.J. (2000) Simultaneous Image Refocusing (SIR): A New Approach to Multi-Slice MRI. Proceedings of 8th Scientific Meeting ISMRM, Denver, April 2000, 681.

[9]   Feinberg, D.A., Moeller, S., Smith, S.M., Auerbach, E., Ramanna, S., Glasser, M.F., Miller, K.L., Ugurbil, K. and Yacoub, E. (2010) Multiplexed Echo Planar Imaging for Sub-Second Whole Brain FMRI and Fast Diffusion Imaging. PLoS One, 5, e15710.
http://dx.doi.org/10.1371/journal.pone.0015710

[10]   Gunther, M. and Feinberg, D.A. (2005) Simultaneous Spin-Echo Refocusing. Magnetic Resonance in Medicine, 54, 513-523.
http://dx.doi.org/10.1002/mrm.20587

 
 
Top